How to focus & concentrate for studies - Tips and guide

How to concentrate in studies main tips, it is because no matter how hard I try, most of the time I am loosing my concentration. I starts a section, and even after whole day its not completed or have not even covered smallest part of it.

Sometimes, I am awake late night to study but I ends up doing nothing. I know if I can do regular studies then can achieve a lot. But can't do that as end up wasting my time. I starts thinking about lots of things, sometimes I just starts doing pending things thinking that its more important than study but later I feel I could have avoided it.

Please give me some good tips about it.